1. Technical Field
This invention generally relates to an apparatus for controlling the feeding of liquid feed to livestock. More particularly, this invention relates to a portable programmable device for the feeding of liquid feed to livestock in controlled quantities and at controlled times.
2. Background Art
A common practice within the livestock industry, is to utilize liquid feed products to provide supplemental nutrients and feed additives to animals. These liquid feeds are manufactured by solubilizing or suspending a wide range of individual ingredients that contain specific nutrients and feed additives within a variety of liquid carriers, such as molasses, fermentation solubles, condensed whey, etc. These finished products are then fed to the animals. There is a wide variation in the application of these liquid feed products as they are fed to variable numbers within the feeding groups as well as various classes, weights and ages of animals. Frequently, it is inconvenient to combine the liquid feed with other feed ingredients prior to feeding, and consequently they must be provided to the animals as a separate ingredient and in a manner in which the animals have unlimited access to the liquid feed in an undiluted form. Unfortunately, it is oftentimes difficult to constrain the animals voluntary intake within a range which provides for maximum response to the nutrients and feed additives. Over feeding of nutrients and additives is wasteful and will adversely affect the return on the feeding investment. Also, animal health and mortality can be affected if the nutrients and feed additives are not provided at the prescribed rate. For this reason there are governmental regulations which specifically control the allowable levels or dose for some nutrients and feed additives. Furthermore, when these feed additives are provided on a basis where the animals are given unlimited access to a feed source in which the additives are included, the manufacturer must provide demonstrable evidence that the average twenty-four hour consumption for the group of animals being fed will provide the feed additive at a level which falls within the required dose range for that particular feed additive.
In addition to the need for regulating the quantity of liquid feed fed, it has also been demonstrated that the timing in which the nutrients and feed additives are provided has an effect on production. For example, it has been demonstrated that cattle grazing on pasture will consume more grass when supplemental feeds are not made available until the afternoon of each day. By consuming more grass, the animals have more energy to support production and this results in an increase in performance and average daily gain for each animal. In a like manner, it has been demonstrated that the death loss which can be associated with cattle grazing legume pasture in a rotational grazing system, can be reduced or eliminated if the cattle consume a liquid feed containing a feed additive which affects the surface tension of gas bubbles formed in the animal's rumen. The ability to control bloat in these applications is enhanced if the cattle consume this additive approximately one hour before they are moved to a new pasture containing the legumes.
It can be seen that there are a wide variety of liquid feed needs from one location to another and the needs change throughout the year. Therefore, there are a wide variety of formulations required to meet these needs and any feeding system must easily accommodate change in regards to quantities being fed, timing at which the liquid feed is made available and varying product composition.
The application of liquid feeds of the type previously described are most often accomplished in remote locations. More often than not, it is economically impractical to provide the labor required for daily hand feeding operations. Because of a lack of convenient access to an AC power source it is necessary to have feeding systems which require no power or which can be operated on a DC power source for long periods of time. The feeding system must also be readily portable as the animals are frequently moved from one confined feeding area to another.
Prior art solutions to the needs described above have generally relied on methods and devices directed towards affecting the quantities of liquid feed being voluntarily consumed as opposed to those directed towards controlling the amount actually dispensed and being made available for voluntary consumption. One common method has been to decrease voluntary intake of the liquid feed by lowering its relative palatability. An example of this approach would be the practice of incorporating increased levels of a specific ingredient such as salt within the liquid feed. This can affect the animals sense of taste in such a way as to sometimes lower the animals voluntary intake. Another method of reducing voluntary intake has been to provide a means for applying increased tension on a revolving lick wheel that is acting as a liquid feed pickup device. This increased tension will result in the animals requiring more time and effort to consume a specified quantity of liquid feed and this may also lower voluntary intake.
The prior art specifically describing liquid feed dispensing devices which can provide a means of controlling the quantity of liquid feed that is dispensed within a specified period of time to one or more animals is lacking. Typically the devices available can be best described as constant flow or constant level devices which allow the animals access to unlimited quantities of liquid feed or they may be designed to provide access to unlimited quantities of liquid feed during specified periods of time. Unlike the invention which we will describe these devices typically utilize a pressurized source of liquids, an AC powered electric control circuit and some type of automated control valve. Additional mechanical elements common to prior art but which also fall outside our invention are pumps, hydraulic cylinders, vacuum valves, air pressure valves, weighing systems, float valves, stopper plugs, metering valves, metering orifices and batch dumping cylinders.
More specifically, U.S. Pat. No. 3,347,212 to ANDERSON ET AL. discloses an apparatus for the feeding of liquid feed to livestock on a continuing output basis. This is accomplished by lowering a flexible hinged transfer tube through a vertical plane in a storage vessel containing liquid feed thereby allowing the liquid feed to gravity flow through the tube and into a liquid feed pickup device. It can then be accessed by the livestock through a lick ball. The device described by this patent utilizes a predicted rate of descent as a means of dispensing liquid feed on a constant flow basis. The rate of descent is controlled through the use of a battery assisted spring wound clockwork motor and integrated unwinding cable working in conjunction with a spool assembly fitted with multiple diameters the use of which allows for selecting differing rates of descent by the drop tube assembly. The element of time in the device described by this patent only has meaning in respect to affecting the rate of descent. As soon as automated feeding is initiated the control means will continue on a basis that is only manually interuptable and therefore the transfer tube will normally continue to drop through the fluid until it rests on the bottom of the supply vessel. Thus it can be seen that the quantity of liquid feed automatically dispensed is totally independent of the liquid feed actually consumed by the livestock during the total dispensing period. This period being the time required to allow the transfer tube to travel from the top of the liquid level to the bottom of the storage vessel. This system has a number of disadvantages as applied under practical feeding situations. The primary deficiency of this invention is that if the voluntary consumption is less than the projected rate the potential consumption is accumulated. This can continue to a point where the total remaining feed in the storage vessel is essentially all available. Therefore, there is no means of protecting the livestock against excessive consumption when there has been a period of time when consumption is less than projected in establishing the rate of decent. This is particularly a problem when the number of cattle placed in a particular feeding area are being changed from one day to the next. This is a common livestock management practice. Another disadvantage of the device described by this patent is that the use of controlled rate of descent as applied in a battery operated system results in a significant opportunity for error. A small difference in the total distance traveled by the transfer tube can make a significant difference in the total quantity of liquid feed dispensed. The effective voltage potential in a battery powered operation can vary significantly depending on the batteries remaining charge or the batteries effective ambient temperature . This drop in voltage output will produce a corresponding drop in revolutions and or a sporadic disfunctioning of the clockwork motor and thereby changes the effective distance of downward travel by the transfer tube. Furthermore, the opportunity for inaccuracy and the lack of an ability to time the feeding periods in a more specific manner give rise to the significant need for our invention.